From the journal "Staub, Reinhaltung der Luft", Volume 46 (1986), pages 120 to 124, a discontinuously operating process for the separation of particles is known. In this process, individual samples of particles, for example electrostatic filter dusts with absorbed heavy metal compounds, are heated together with a flowing gaseous carrier medium to comparatively high temperatures. Constituents of these particles, especially the heavy metal compounds, vaporize and form a vapor/gas mixture with the carrier medium. This vapor/gas mixture is then cooled until the vaporized constituents condense. The condensate can be used for analytical purposes. The apparatus used for this separation consists of a fan which moves the carrier medium over the particles introduced batchwise into the heating device. The vapor/gas mixture formed in the heating device is cooled in a downstream cooler.
The process described above and the apparatus for carrying it out are only suitable for laboratory operation in order to obtain very small quantities of condensate for analysis. Moreover, the time and energy expended on this process are comparatively high, so that large-scale industrial application of the process would be uneconomical.